There are a number of different known configurations for steam dispersion humidification systems. One known configuration utilizes a plurality of closely spaced steam dispersion tubes with steam dispersion nozzles for emitting steam. The plurality of steam dispersion tubes extend across the air duct and provide humidification steam to air flowing therethrough.
The plurality of steam dispersion tubes may extend from a central steam manifold such as a header. In certain configurations, the steam dispersion tubes may extend from a header at one end and be attached to the duct wall at the other end, usually through a bracket or a frame. In certain other configurations, the steam dispersion tubes may be positioned between two headers supplying steam to the tubes.
In most conventional systems, attachment of the steam dispersion tubes, either to the header(s), or to the duct, may be a cumbersome and a time-consuming process, requiring many steps, a large number of parts and tools.
For example, in one conventional method of attachment, holes are first drilled into a header wall. Lengths of tubing are cut into short stubs (e.g., 3 inch stubs). The stubs are aligned with the holes drilled into the header and welded at each stub-to-header joint. The walls of the header might warp from the heat caused by the welding, and, thus, might need to be straightened out. Once the stubs are welded onto the header, either a plastic coupling piece or a hose cuff (i.e., a short piece of hose, for example, 2 inches in length) is slid over each of the stubs. The plastic couplings may be shaped in an inner diameter portion thereof to seat a number of sealing structures such as O-rings, gaskets, etc., to provide a seal with outer diameter of the stubs. The plastic couplings may be friction-fitted onto the stubs. In the case of hose cuffs, hose clamps may be used.
The elongate steam dispersion tubes are slid into the other end of the plastic couplings or the hose cuffs and are sealed with sealing structures such as O-rings, gaskets, etc. Again, a friction fit for the plastic couplings or hose clamps for the hose cuffs may be used for attachment.
In a single header system, the other end of the steam dispersion tubes may be attached to the duct wall through a frame or a bracket. A cap may be welded to the other end of the steam dispersion tube. A nut may be welded to the cap. From thereon, a bolt and a L-bracket may be used to attach the end of the steam dispersion tube to the duct wall.
As described above, conventional spring dispersion tube attachment techniques are cumbersome, time-consuming, and require a large number parts and tools. The lengths of the parts including the stubs and the dispersion tubes have to be cut accurately to provide for correct fitment. Thermal expansion of the parts may lead to failure of the seal joints. Moreover, if the tubes need replacing, detachment thereof may be as cumbersome as their attachment.
Other attachment methods providing convenient and quick mounting of steam dispersion tubes to a steam dispersion system, while providing strong seals, are desired.